Oropharyngeal Airway

ABSTRACT

An oropharyngeal device for insertion into the mouth of a patient. The device includes a body having a distal end and a proximal end with a flange formed at the proximal end. The distal end of the body is inserted into the mouth of the patient until the flange at the proximal end is disposed outside and adjacent to the patient&#39;s mouth. The flange keeps the proximal device from entering the mouth. The body is sized such that the distal end of the body is disposed within the pharynx above the epiglottis. The device includes a channel through the body that forms an airway between its proximal and distal ends. The device also includes at least three separate conduits integrated into the body for administering oxygen, suctioning, and for assessing ventilation through end-tidal carbon dioxide monitoring. The conduits for oxygenation and suctioning extend through the body between its proximal and distal ends. The conduit for end-tidal carbon dioxide monitoring extends along and is attached to a side wall of the channel and terminates within the channel.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present invention is related to and claims priority from co-pendingU.S. patent application Ser. No. 10/666,290 filed Sep. 19, 2003 and fromU.S. Provisional Patent Application Ser. No. 60/413,174, filed Sep. 14,2002, both being incorporated by reference herein in their entirety.

FIELD OF THE INVENTION

The invention relates to establishing and maintaining an airway and, inparticular, to an oropharyngeal device for establishing and maintainingan airway.

BACKGROUND OF THE INVENTION

The administration of anesthesia via a face mask technique usuallyrequires continuous hands-on management. This is inconvenient duringcertain medical procedures that require access to the face because theface mask technique may obstruct access to the face.

For example, access to the face may be necessary for ophthalmologicexamination, radiation therapy, MRIs (magnetic resonance imaging), andCT (computed tomography) or CAT (computed axial tomography) scans. If amask is used to administer anesthesia during such procedures, access thepatient's face may be hindered. Further, in such circumstances,anesthesiologists often use awkward hand positioning to allow access tothe face which then requires repeated manipulation of the mask to ensurea patent airway.

The administration of anesthesia via a face mask technique is alsoinconvenient when the anesthesiologist must be distant from the patientsuch as during radiation therapy, CT or CAT scans, and during MRIs.Although the anesthesiologist may repeatedly instrument the trachea insuch circumstances, the stimulation may result in irritation of thetrachea especially when treatment is necessary on an on-going basis. Forexample, during radiation therapy, patients may be repeatedly treatedeach day over a period of several weeks. Repeated instrumentation duringthis on-going treatment will irritate the patient's trachea and mayresult in other adverse consequences such as a sore throat and loss ofappetite due to the irritated trachea and hypopharynx.

The above situations are conventionally resolved by using generalanesthesia with endotracheal intubation, by using intravenous techniqueswithout securing the airway with adjunctive devices, by using alaryngeal mask airway (LMA), or by using a cuffed oropharyngeal airway(COPA). Each of these solutions has its respective drawbacks especiallyduring procedures such as radiation treatment where deep anesthetizationis not necessary, where the patient breathes by himself and wheretreatment is on an on-going basis.

An endotracheal tube may be used to deliver anesthetic gases and tomaintain a patient's airway. Endotracheal intubation is very stimulatingbecause the endotracheal tube extends through the vocal chords and intothe trachea. This requires that the patient be deeply anesthetized orpartially paralyzed with neuromuscular blocking agents to keep him fromreaction to the intubation. Thus, endotracheal intubation is notdesirable for circumstances that do not require deep anesthetization.Endotracheal intubation also subjects the patient to laryngoscopy forinserting the endotracheal tube and to tracheal irritation which makesit undesirable for circumstances requiring repeated instrumentation.Generally, endotracheal intubation is better suited for more invasiveprocedures when the patient is deeply anesthetized and not responsive tothe stimulation caused by the endotracheal tube and can not breathe onhis own.

Intravenous techniques may obviate the use of inhalational agents, butstill necessitate maintenance of a patent airway. Moreover, end-tidalcarbon dioxide monitoring may be desirable in addition to supplementaloxygen during total intravenous anesthesia. Further, suction cathetersmust be introduced to suction secretions from the patient's pharynx.

An LMA may be used to provide oxygen to a patient and to monitorend-tidal carbon dioxide and is less invasive than an endotracheal tubebecause it does not go through the patient's vocal chords. However, theLMA must be connected to a conventional anesthesia circuit, does notprovide a mechanism for suctioning secretions, and requires technicalfacility for its insertion that may require adjunctive equipment for itsapplication. Further, the LMA is very stimulating because it includes acuff that inflates in the patient's trachea to prevent reflux from thestomach from entering the trachea. This stimulation is undesirable incircumstances requiring repeated instrumentation.

A COPA is a device consisting of an airway with a cuff. A COPA devicemay be used to provide oxygen to a patient and to monitor end-tidalcarbon dioxide. However, the COPA must be connected to a conventionalanesthesia circuit or to an adapter to connect the COPA to an oxygensource and may cause the patient discomfort due to the inflated cuff.Further, the COPA does not include a suctioning mechanism which mayresult in a medical procedure being interrupted in order for ananesthesiologist to suction the patient when secretions are building up.

For the administration of anesthesia, there is a need for a device thatwill maintain a patent airway while providing the capability tooxygenate the patient, to provide suctioning, and to monitor end-tidalcarbon dioxide. Further, there is a need for such a device that isminimally stimulating to allow for repeated use during on-goingtreatments, that does not block access to the face of a patient, andthat allows an anesthesiologist to be distant from the patient.

SUMMARY OF THE INVENTION

The invention provides an oropharyngeal device for insertion into themouth of a patient. The device includes a body having a distal end and aproximal end. The device body is sized such that when the distal end ofthe body is inserted into the mouth of the patient until the proximalend is disposed outside and adjacent to the patient's mouth, the distalend is disposed within the pharynx above the epiglottis. At least onechannel extends between the proximal end and the distal end of thedevice body to form at least one airway in the device body. Inhalant gasmay be conveyed to the patient via at least one first conduit thatextends from the proximal end to the distal end of the device body.Suctioning may be applied via at least one second conduit that extendsfrom the proximal end to the distal end of the device body. End-tidalcarbon dioxide of gas exhaled by the patient may be monitored via atleast one third conduit that extends from the proximal end of the devicebody and terminates at a position within the channel.

The invention also provides a method of establishing and maintaining anairway of a patient. The oropharyngeal device described above isinserted into the mouth of the patient until the proximal end is outsideand adjacent to the patient's mouth. An inhalant gas source, asuctioning device, and a gas sampling device are connected to the first,second, and third conduits, respectively.

For purposes of illustrating the invention, the distal end of the deviceshall refer to the end which penetrates into the patient's airway(marked 106 in FIGS. 1 and 206 in FIG. 2). The proximal end shall referto the end which is held adjacent to the mouth (marked 104 in FIGS. 1and 204 in FIG. 2). The terms “proximal” and “distal” with respect toorientation and direction in the patient's airway shall mean,respectively, the directions toward and away from the patient's mouth.

BRIEF DESCRIPTION OF THE FIGURES

For the purpose of illustrating the invention, there is shown in thedrawings a form that is presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand instrumentalities shown.

FIG. 1A is an isometric view of an oropharyngeal device according to thepresent invention;

FIG. 1B is a cross-sectional view of the oropharyngeal device shown inFIG. 1A taken along line 1B-1B;

FIG. 1C is a cross-sectional view of the oropharyngeal device shown inFIG. 1A taken along line 1C-1C;

FIG. 1D is a cross-sectional view of the oropharyngeal device shown inFIG. 1A taken along line 1D-1D;

FIG. 1E is a sagittal view of a patient showing the oropharyngeal deviceof FIG. 1A inserted into the mouth of the patient;

FIG. 2A is a front isometric view of an oropharyngeal device accordingto the present invention;

FIG. 2B is a rear isometric view of the oropharyngeal device shown inFIG. 2A;

FIG. 2C is a front view of the proximal end of the oropharyngeal deviceshown in FIG. 2A without the conduits extending from the proximal end ofthe device;

FIG. 2D is a sagittal view of a patient showing the oropharyngeal deviceof FIG. 2A inserted into the mouth of the patient;

FIGS. 3A-3C are three cross-sectional views of the oropharyngeal deviceshown in FIG. 2A taken along line 3-3 in FIG. 2A illustrating threedifferent lengths of the third conduit;

FIG. 4A is an isometric view of an oropharyngeal device according to thepresent invention;

FIG. 4B is a cross-sectional view of the oropharyngeal device shown inFIG. 4A taken along line 4B-4B;

FIG. 4C is a front view of the proximal end of the oropharyngeal deviceshown in FIG. 4A without the conduits extending from the proximal end ofthe device;

FIG. 5A is an isometric view of an oropharyngeal device according to thepresent invention;

FIG. 5B is a cross-sectional view of the oropharyngeal device shown inFIG. 5A taken along line 5B-5B;

FIG. 6A is an isometric view of an oropharyngeal device according to thepresent invention;

FIG. 6B is a front view of the proximal end of the oropharyngeal deviceshown in FIG. 6A; and

FIG. 6C is a cross-sectional view of the oropharyngeal device shown inFIG. 6A taken along line 6C-6C.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings in which like reference numerals indicate likeelements, there is shown in FIGS. 1A-E an oropharyngeal device 100according to an exemplary embodiment of the present invention. Thedevice 100 includes a body 102 having a proximal end 104 and a distalend 106.

A channel 108 forms an airway through the body 102 that extends throughthe body 102 from its proximal end 104 to its distal end 106. Asillustrated in FIG. 1E, the body 102 is sized such that when the distalend 106 of the body 102 is inserted into the mouth 152 of a patient 150until the proximal end 104 is disposed outside and adjacent to thepatient's mouth 152, the distal end 106 of the body 102 is disposedwithin the pharynx 154 above the epiglottis 156. The body 102 may beformed of a rigid material to serve as a bite block to prevent thepatient from biting any conduits inserted through the channel.

The airway channel may be completely enclosed within the body of theoropharyngeal device, as illustrated by channel 108. Alternatively, oneor more channels may be formed by a ridge, flange or protrusion runningthe length of the body, as illustrated by channels 508 and 509 in FIGS.5A and 5B.

The device 100 includes three conduits 110, 112, 114 that may be usedduring the administration of anesthesia. The first conduit 110 is forconveying an inhaling gas to the patient 150. Conduit 110 extends fromthe proximal end 104 to the distal end 106 of the body 102. The secondconduit 112 is for suctioning. It also extends from the proximal end 104to the distal end 106 of the body 102. The third conduit 114 is forsampling gas exhaled by the patient 150. Conduit 114 extends in thechannel 108 from the proximal end 104 of the body 102 and terminates ata position 116 in the channel 108. Conduit 114 extends to a position 116within the channel 108 that corresponds to the location of the mouth ofthe patient 150, when the device is inserted.

Although the body 102 is illustrated in FIGS. 1A-E as having arectangular cross-section, the body 102 may alternatively be formed inother shapes including a body having an oval, round or squarecross-section. The channel 108 is also illustrated in FIGS. 1A-E ashaving a rectangular cross section and may also be formed in othershapes, not necessarily the same shape as the body 102. Similarly,although the first, second, and third conduits 110, 112, 114 areillustrated as having round cross-sections, they too may beindependently formed in other shapes.

In the embodiment illustrated in FIGS. 1A-E, the first and secondconduits 110, 112 are formed within the body 102 and the third conduit114 is formed within the channel 108. Alternatively, each conduit 110,112, 114 may be formed either within the body 102, within the channel108, or partially within the body 102 and partially within the channel108.

A further embodiment of the oropharyngeal device of the invention isshown in FIGS. 2A-2D. The oropharyngeal device 200 includes a flange 220at the proximal end 204 of the body 202. As illustrated in FIG. 2D, thedistal end 206 of the body 202 is inserted into the mouth of a patient250 such that the proximal end 204 of the body 202 is outside andadjacent to the patient's mouth 252. The flange 220 abuts the entranceof the patient's mouth and serves to prevent the oropharyngeal device200 from further proceeding into the patient's mouth.

In certain embodiments of the invention, the third conduit 214 (forsampling patient exhaled gas) is contained in channel 208. In suchembodiments, the third conduit 214 may terminate at various positionswithin the channel 208. FIGS. 3A-C are cross-sectional views of theoropharyngeal device 200 taken along line 3-3 in FIG. 2A whichillustrate various positions within the channel 208 at which the thirdconduit 214 may terminate. Although end-tidal carbon dioxide isoptimally monitored at the distal end 206 of the device body, a thirdconduit 214 having its distal end positioned at or terminating at thedistal end 206 of the device body may be clogged by secretions. In FIG.3A, the third conduit 214 a extends from the proximal end 204 of thebody 202 to a position 316 a within the channel 208 located in themiddle-third 302 of the body 202. In this central position 302, thethird conduit 214 a terminates at a position distant from the proximalend 204 for better gas sampling and at a position distant from thedistal end 206 to avoid clogging. The third conduit 214 b shown in FIG.3B extends from the proximal end 204 of the body 202 to a position 316 bwithin the channel 208 located within the first-third 301 of the body202 as measured from the proximal end 204. The third conduit 214 c shownin FIG. 3C extends from the proximal end 204 of the body 202 a to aposition 316 c within the channel 208 located in the farthest-third 303of the body 202 as measured from its proximal end 204.

The oropharyngeal device may include more than three conduits, wheremore than one inhalant gas conduit, suctioning conduit, or exhalationgas sampling conduit is present. The oropharyngeal device 400 shown inFIGS. 4A-C includes two conduits 410, 411 for administering an inhalantgas which may be used, for example, to separately administer twodifferent inhalant gases or to administer a larger volume of a singleinhalant gas. The oropharyngeal device 400 includes two conduits 414,415 for sampling exhalant gas which may each be coupled, for example, toa different device for sampling different components of the exhalantgas. Alternatively, the second conduits 414, 415 may be used in aredundant fashion where one serves as the active conduit and the otherserves as the standby conduit. In the event that the active conduitceases to function as a result of clogging, for example, the standbyconduit may instead be used to sample the exhalant gases.

As illustrated in FIG. 4B, the conduit 414 for sampling exhalant gasesextends entirely within the channel 408 from the proximal end 404 of thebody 402 to a position 416 where it terminates within the channel 408.The other conduit 415 for sampling exhalant gases is formed within thebody 402 and extends from the proximal end 404 of the body 402 andterminates at a position 418 within the channel 408.

The present invention may be applied to oropharyngeal devices havingbodies of various shapes. For example, the oropharyngeal device 500shown in FIG. 5A includes two U-shaped channels 508, 509 formed within abody 502 having an I-shaped cross-section.

The oropharyngeal device 500 includes a first conduit 510 foradministrating an inhalant gas that extends through the body 502 fromits proximal end 504 to its distal end 506. A second conduit 512 forsuctioning also extends through the body 502 from its proximal end 504to its distal end 506. A third conduit 514 for sampling exhalant gasesis formed adjacent to a sidewall 520 of the channel 509 and extends fromthe proximal end 504 of the body 502 to a position 516 within thechannel 509.

To facilitate connection and disconnection of conventional devices suchas inhalant gas sources, gas sampling devices, and suctioning devices tothe conduits of an oropharyngeal device according to the presentinvention, the oropharyngeal device may include standard connectors forconnecting to such devices. The connectors may be connected to thefirst, second, and third conduits at the proximal end of the body.Alternatively, as shown in FIGS. 6A-C, the oropharyngeal device 600 mayinclude flexible hoses, 632, 634, 636 coupled to the ends of the first,second, and third conduits 610, 612, 614, respectively, at the proximalend 604 of the body 602. The ends of the flexible hoses 632, 634, 636may include connectors 638, 640, 642.

During some medical procedures the mouth of the patient may be coveredand it may be desirable for the hoses 632, 634, 636 or connections toother devices be coupled to the oropharyngeal device 600 from the side.In such cases, a right-angle connector 644 may be used to connect aconduit 612 to the hose 634. Alternatively, instead of the conduits 610,612, 614 extending to the proximal end 604 of the body 602, the conduitsmay exit a side of the body 602 adjacent to the proximal end 604 or mayexit through the side of the flange.

An oropharyngeal device according to the present invention allows formaintenance of an airway while simultaneously administering an inhalantgas, suctioning, and sampling an exhalant gas. This is possible withoutobstructing access to the face of a patient because first, second, andthird conduits for each purpose are integrated into the device. Thisfacilitates the administration of anesthesia during treatment of apatient's head or neck despite lack of or obstructed access to thepatient's mouth, face, or airway. In the event that mechanicalventilation or “positive pressure” is required to augment a patient'sbreathing while an oropharyngeal device according to the presentinvention is in use, a mask for providing mechanical ventilation may beapplied over the device and the patient's mouth.

The oropharyngeal device is sized to terminate above or proximal to thepath of travel of the epiglottis and avoids manipulation of the larynxand subglottic structures. This avoids increased stimulation and avoidsmedical complications associated with devices which may impinge on orcause damage to the delicate laryngeal and supra-laryngeal structuresand makes the oropharyngeal device suitable for circumstances requiringrepeated use such as during on-going radiation treatment. A patient maybe taken to a recovery area with the oropharyngeal device still inposition and it can then be easily removed as the patient awakens, withvery little discomfort to the mouth or throat.

The oropharyngeal device may be inserted in a similar fashion toconventional oropharyngeal airways and thus is simple to apply, does notrequire extensive training or instruction to use, and does not requireany special or additional equipment such as an anesthesia circuit.Further, the device is recognizable as an anesthesia device and will bereadily acceptable to anesthesia personnel. The device may be used toassist in the placement of an endotracheal tube by inserting a fiberoptic scope device in the channel for placing the endotracheal devicethrough or adjacent to the oropharyngeal device.

All documents referred to herein are incorporated by reference. Whilethe present invention has been described in connection with thepreferred embodiments and the various figures, it is to be understoodthat other similar embodiments may be used or modifications andadditions made to the described embodiments for performing the samefunction of the present invention without deviating therefrom.Therefore, the present invention should not be limited to any singleembodiment, but rather should be construed in breadth and scope inaccordance with the recitation of the appended claims.

1. An oropharyngeal device for insertion into the mouth of a patientcomprising: a. a body having a distal end and a proximal end, the bodysized such that when the distal end of the body is inserted into themouth of the patient until the proximal end is disposed outside andadjacent to the patient's mouth, the distal end is disposed within thepharynx above the epiglottis; b. at least one channel forming at leastone airway in the device body extending between the proximal end and thedistal end of the device body; c. at least one first conduit in thedevice body for conveying an inhalant gas to the patient that extendsfrom the proximal end to the distal end of the device body; d. at leastone second conduit for suctioning that extends from the proximal end tothe distal end of the device body; and e. at least one third conduit forsampling gas exhaled by the patient that extends from the proximal endof the device body and terminates at a position in the channel.
 2. Theoropharyngeal device according to claim 1 wherein at least one of the atleast one first, second, and third conduits is disposed within thedevice body.
 3. The oropharyngeal device according to claim 1 whereinthe at least one first, second, and third conduits are independentlydisposed within the at least one channel.
 4. The oropharyngeal deviceaccording to claim 1 wherein the at least one first, second, and thirdconduits are independently disposed partly within the device body andpartly within the at least one channel.
 5. The oropharyngeal deviceaccording to claim 1 wherein the third conduit terminates at a positionwithin the channel corresponding to the mouth of the patient.
 6. Theoropharyngeal device according to claim 1 wherein the device body has alength from its proximal end to its distal end and the at least onethird conduit terminates within the channel at a location within theo-thirds of the device body length closest to the proximal end of thedevice body.
 7. The oropharyngeal device according to claim 1 whereinthe at least one channel has a U-shaped cross section.
 8. Theoropharyngeal device according to claim 1 wherein the at least onechannel has a closed cross section.
 9. The oropharyngeal deviceaccording to claim 1 wherein the device is rigid and functions as a biteblock.
 10. The oropharyngeal device according to claim 1 wherein thefirst, second, and third conduits each independently have an insidediameter between 2 mm and 5 mm.
 11. The oropharyngeal device accordingto claim 1 wherein the first, second, and third conduits are coupled toconnectors at the proximal end of the device for connecting to aninhalant gas source, a suctioning device, and a gas sampling device,respectively.
 12. The oropharyngeal device according to claim 1 furthercomprising at least one flexible extension conduit coupled to at leastone of the first, second, and third conduits at the proximal end of thedevice body.
 13. The oropharyngeal device according to claim 1 furthercomprising a flange at the proximal end of the device for preventing theproximal end of the device body from entering the mouth.
 14. Theoropharyngeal device according to claim 1 further comprising at leastone right-angled connector coupled to at least one of the first, second,and third conduits at the proximal end of the device wherein theright-angled connector bends at a right angle with respect to a surfaceof the device body at its proximal end.
 15. The oropharyngeal deviceaccording to claim 6 wherein the at least one channel has a closed crosssection, the at least one first conduit is disposed within the devicebody, and the at least one second conduit is disposed within the devicebody.
 16. A method for establishing and maintaining an airway comprisingthe steps of: a. inserting the device according to claim 1 into themouth of the patient until the proximal end is outside of and adjacentto the patient's mouth; b. connecting at least one inhalant gas sourceto the at least one first conduit; c. connecting at least one suctioningdevice to the at least one second conduit; and d. connecting at leastone gas sampling device to the at least one third conduit.